Conversion Electrons Moessbauer Spectroscopy applied to study of Iron Corrosion Products under artificial atmosphere of SO2

ICEMS (Isotope Conversion Electrons Moessbauer Spectroscopy) technique was employed in the identification of the corrosion grown on a commercial steel sample exposed to [SO2] 0,22% v/v and 98% RH corrosive atmosphere. FeSO33H2O was identified as the dominant compound in the early corrosion stage (2 h). For longer exposition times (12 and 24 h) ferric oxy hydroxides (a-FeOOH spm and g-FeOOH) were dominant. The study of the transformation sequence of these compounds shows a surprising diminution of the weight gain at 24 and 48 hours, likely because of a dehydration process